The inside is made of aluminum material, providing cold and heat retention. Features a zipper and an outer pocket. Has a gusset. Size: 22 x 20 x 13 cm All items include free shipping (price includes shipping). You can purchase directly without commenting. Usually, items will be shipped via regular mail from Sapporo within 3 business days after payment is received. Shipping is done on Mondays, Wednesdays, and Fridays, excluding holidays. We are closed on Tuesdays, Thursdays, Saturdays, Sundays, and holidays. (We are unable to respond to questions or transaction messages during these days.) Delivery is expected within 4 business days after shipping, excluding weekends and holidays. There is no tracking number. If you are not home and the item does not fit in your mailbox, a notice from Japan Post will be left, and the item will be held at your local post office for one week. Please check the notice and request redelivery from Japan Post. If you cannot find the notice, please contact your local post office before the storage period expires. We are sorry, but we do not accept any price negotiations. Please understand that all items listed are not subject to price reduction. We will block any comments requesting unreasonable price reductions. If multiple items are purchased and can be shipped together, we will do so as much as possible, but we will not offer a discount in that case either. Also, we do not accept requests for additional images.